Silicon Photonics is a promising technology for reducing the cost structure of various optical components by leveraging the economies of scale of the microelectronics industry. In the same way as silicon CMOS circuits can be packaged using multiple die, then in principle so can silicon photonics devices. In order to optically interconnect a silicon photonics device to another device, various light energy transfer approaches have been developed based either on near field, far field or adiabatic coupling. Only near field edge coupling can provide for both low loss as well as for polarization diversity. However, to date, the packaging of photonic integrated circuits to support edge coupling has been restricted to active assembly and thus slow and very expensive as requiring light to perform the alignment. The passive packaging of silicon photonics devices has thus far been restricted to applications where higher optical losses can be tolerated. Even with the most innovative waveguide tapers, inverse tapers and mode (spot) size converters to perform mode field conversion and mode field diameter matching, it has been impossible up to now to perform the passive packaging of telecom grade photonic integrated circuits.
Silicon microelectromechanical systems (MEMS) are small integrated devices or systems that combine electrical and mechanical components within a single silicon die, although other material systems may be employed. The components can range in size from the sub-micrometer level to the millimeter level, and there can be any number, from one, to few, to potentially thousands or millions, in a particular system. Historically, MEMS devices have leveraged and extended the fabrication techniques developed for the silicon integrated circuit industry, namely lithography, doping, deposition, etching, etc. to add mechanical elements such as beams, gears, diaphragms, and springs to silicon circuits either as discrete devices or in combination with silicon electronics. Examples of MEMS device applications today include inkjet-printer cartridges, accelerometers, miniature robots, micro-engines, locks, inertial sensors, micro-drives, micro-mirrors, micro actuators, optical scanners, fluid pumps, transducers, chemical sensors, pressure sensors, and flow sensors. These MEMS systems can sense, control, and activate mechanical processes on the micro scale, and function individually or in arrays to generate effects on the macro scale and have become a successful actuating technology.
Accordingly, it would be beneficial to combine silicon MEMS based micro-actuators with silicon CMOS control and drive circuits in order to provide alignment of elements within a silicon optical circuit either with respect to each other or with other optical elements hybrid integrated with the silicon optical circuit. In this manner, active alignment of input and output SOI waveguides to an InP optical gain chip (or other SOI circuit) may be provided which may be either maintained as active during deployment of the optical component comprising these elements or removed once the alignment has been “locked” through an attachment/retention/latching process.
Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.